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 A229871 Number of 4X4 0..n arrays with corresponding row and column sums equal 1
 2432, 384183, 15106048, 266515625, 2805425280, 20610104767, 116211580928, 535021318017, 2098414000000, 7227967108439, 22362655260672, 63219695614153, 165498794685056, 405459218109375, 937601561264128, 2060839403682497 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 4 of A229870 LINKS R. H. Hardin, Table of n, a(n) for n = 1..73 FORMULA Empirical: a(n) = (29/140)*n^13 + (377/140)*n^12 + (3449/210)*n^11 + (13057/210)*n^10 + (34249/210)*n^9 + (21941/70)*n^8 + (6826/15)*n^7 + (53206/105)*n^6 + (60773/140)*n^5 + (119003/420)*n^4 + (28807/210)*n^3 + (9791/210)*n^2 + (348/35)*n + 1 EXAMPLE Some solutions for n=4 ..0..0..0..0....0..0..0..1....0..0..0..1....0..0..1..1....0..0..1..1 ..0..1..2..3....0..0..4..2....0..1..1..3....0..1..2..1....0..1..0..2 ..0..4..0..0....1..4..0..1....1..4..2..0....1..3..4..3....1..2..0..0 ..0..1..2..3....0..2..2..3....0..0..4..3....1..0..4..1....1..0..2..0 CROSSREFS Sequence in context: A186874 A202201 A147984 * A192767 A250710 A278196 Adjacent sequences:  A229868 A229869 A229870 * A229872 A229873 A229874 KEYWORD nonn AUTHOR R. H. Hardin, Oct 01 2013 STATUS approved

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Last modified October 23 23:51 EDT 2019. Contains 328379 sequences. (Running on oeis4.)